Internal Resonances for the Heave Roll and Pitch Modes of a Spar Platform Considering Wave and Vortex Exciting Loads in Heave Main Resonance

The objective of this paper is to study the nonlinear coupling internal resonance of the heave, roll, and pitch response performance of a spar platform when their frequencies are in the ratio of 2:1:1 under wave and vortex exciting loads. The three degree-of-freedom (DOF) nonlinear coupled equations are established by considering a time-varying wet surface with a first-order wave force in heave and pitch and a vortex-induced force in roll. The first-order steady-state response is solved using the multi-scale method in heave main resonance. The multiple solutions of the motion equations are discussed using the analytic method and a numerical simulation. A sensitivity analysis is conducted to test the influence of the damping and internal detuning parameter. The regions of multiple solutions are found, and the jump phenomenon exists with the changes of the wave excitation. The regions of multiple solutions depend on the values of damping and detuning parameter.     

波激和涡激Spar平台在垂荡主共振时垂荡、横摇和纵摇内共振响应（英文）

The objective of this paper is to study the nonlinear coupling internal resonance of the heave, roll, and pitch response performance of a spar platform when their frequencies are in the ratio of 2:1:1 under wave and vortex exciting loads.The three degree-of-freedom(DOF) nonlinear coupled equations are established by considering a time-varying wet surface with a first-order wave force in heave and pitch and a vortex-induced force in roll. The first-order steady-state response is solved using the multi-scale method in heave main resonance. The multiple solutions of the motion equations are discussed using the analytic method and a numerical simulation. A sensitivity analysis is conducted to test the influence of the damping and internal detuning parameter. The regions of multiple solutions are found, and the jump phenomenon exists with the changes of the wave excitation. The regions of multiple solutions depend on the values of damping and detuning parameter.     

潜堤对平均沿岸流及沿岸流不稳定的影响

潜堤是防止海岸侵蚀的常用护岸建筑物,准确的掌握潜堤前后水动力特性十分必要.本文以斜坡上梯形潜堤为研究对象,基于港池沿岸流实验,通过变换潜堤的位置来分析潜堤对平均沿岸流的影响,通过增加潜堤来观察其对沿岸流不稳定波动频率的影响.结果表明,潜堤离岸越近,垂直岸方向的沿岸流分布有向岸偏移的趋势,同时,会使得沿岸方向上游流速增加越大,使总的沿岸方向的流速分布更均匀;增加潜堤会使沿岸流不稳定某些频率的波动明显加强,同时也会使沿岸流不稳定波动出现新的高频部分.     

锂离子电池电解液研究进展

本文着重介绍了锂离子电池电解液中溶剂、锂盐及添加剂的性能、优缺点及改进方法,并对这些材料的应用作了进一步展望。     

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化子闸泵站是姚江二通道(慈江)东排工程的梯级泵站之一,其主要任务是加大姚江干流东排分洪能力,提升江北、镇海片防洪排涝能力。泵站设计流量150 m3/s,设计净扬程仅0.32 m,属大流量超低扬程泵站。从水力性能、工程投资、施工和运行管理等方面综合比较,选用了竖井贯流泵装置,TJ04-ZL-07号水力模型。叶轮直径3.9 m,转速60 r/min,是目前国内最大口径和最低转速的竖井贯流泵装置。水泵结构设计的关键点是水导轴承,要求有较好的承载耐磨能力,并且在特低转速下能够形成油膜。经计算分析表明,选用巴氏合金油润滑轴承可满足安全运行要求。     

施工项目成本控制方法探讨

介绍了建筑施工企业在市场竞争中,要立于不败之地,必须遵循的施工项目成本控制的原则和施行的施工项目成本控制的有效途径。     

无线局域网技术概述

论述了近年来发展迅速的无线局域网技术,介绍了其历史、特点、相关技术及应用,提出无线局域网的结构,并通过实际工程案例,介绍了相关的知识。     

高速公路入口匝道的模糊逻辑控制及辅助方案设计

为保证高速公路主线安全、畅通与舒适运行,减少对相连道路的影响,构造了匝道逻辑模糊控制器,提出了三种入口匝道辅助设计方案。结合工程实际,选择了上游车流密度、下游车流密度和入口处等待车辆的总长度作为模糊控制器的输入量,入口匝道的调节率为输出量。计算结果表明,随着入口匝道车辆数量的增加,高速公路主线下游的车速将明显下降,根据主线上、下游车流密度及匝道车辆的数量变化,计算出不同的匝道调节率,通过对高速公路入口匝道的调节率进行实时调节,可控制匝道上车辆的进入,入口匝道辅助方案的实施可缓解与高速公路相连道路的拥堵,对改善高速公路运行安全和效率具有重要的作用。     

郑州黄河公路二桥设计

通过介绍京珠国道主干线郑州黄河公路二桥桥位的选择、桥型方案比选和主桥下承式钢管混凝土系杆拱桥的结构设计和施工方案．对类似的工程施工具有重要的参考价值。     

基于Flexsim的混流生产线生产顺序仿真

阐述了混流生产线的生产顺序问题。基于Flexsim对某订单需求下混流生产线不同生产顺序进行仿真。简要介绍了Flexsim在混流生产线建模仿真过程中的基本步骤和关键技术。通过对仿真结果的分析,得出该订单需求下合理的生产顺序。